Aneeta Brown is a freelance writer and photographer from Washington, Missouri. Her articles have appeared in several national publications including the Washington Post, Family Circle, Woman’s Day and more. Contact her at missouriwriter@yahoo.com.

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Late Pruning for Forsythia by Aneeta Brown

If you missed the ‘window’ of pruning your forsythia immediately after bloom, you might want to wait until the fall. Here’s why.

Best Case Scenario

The proper time to prune Forsythia spp. is immediately after flowering, removing the oldest thickest branches. This is called “rejuvenation pruning” and it allows light and air to enter the center of the shrub and makes room for new young shoots. General pruning guides suggest removing only about one quarter to one third of the total number of branches at a time.

Avoid pruning forsythias into hedges or rounded shapes. These shrubs naturally grow with arching branches in an irregular, rounded shape. Shearing forsythia will destroy many of the flowering branch tips.

If you have a shrub that looks neglected, unkempt and no longer flowers, consider a renewal pruning in spring. Renewal pruning involves removing all branches, leaving only 3 to 4 inch stubs at ground level. While it sounds severe, new shoots will emerge quickly, and flowering should resume the following year.

—Michelle Byrne Walsh, editor

Forsythia’s fast growth and year-round hardiness make it an ideal landscaping shrub, whether planted alone, in a group, or as a living privacy fence. Forsythia’s sunny blooms make a dramatic statement: Spring has arrived! But as fall approached two years ago, our 22 mature shrubs were a mess. Their leggy branches even interfered with the growth and appearance of nearby trees.

I knew they needed pruning, but my research revealed that forsythia should be pruned immediately after spring flowering to ensure full blossoms the following year. We’d missed the deadline. Were there any options? I asked two experts.

You can prune forsythia in the fall, but it must be done before a hard frost, explained Chip Tynan, manager of the Horticultural Answer Service at the acclaimed Missouri Botanical Garden in St. Louis. “Severe fall pruning does create a risk,” he added, “as it can predispose certain plants to winter mortality in the event of extreme cold. With or without pruning, however, we’ll have some springs when forsythia blooms poorly or even fails to flower due to cold weather damage during winter.”

There are several species of Forsythia, and most are native to Asia. The forsythia species grown for landscapes are often Forsythia suspensa or hybrids (Forsythia x intermedia), which are generated from crosses. There are numerous cultivars available to gardeners, some as tall as 10 feet, others dwarfs barely reaching 4 feet tall.

These are the forsythia shrubs in the fall. Note that the pruning thinned out the plants.

Then I called Tim Kriete, who had been pruning trees and shrubs for 35 years at Hillermann Nursery and Florist in Washington, Mo. “If you’re doing the job yourself, use pruning shears to cut the larger canes at the base of the shrub,” he later demonstrated in our yard. “You’ll want to remove one-third of the canes from each plant. Choose the thickest ones. They’re the oldest, and new shoots will sprout from those cut canes. It’s not necessary to apply any seal to the cut.”

When the oldest canes were severed a few inches above the ground and placed in a debris pile, he showed me how to trim the top branches with hand shears. One advantage to fall pruning is that tangled branches are very visible and much easier to handle than when they are filled with leaves or flowers.

This photo, taken the following spring, shows the blooms — not as many as in years past, but not too bad.

By midsummer the shrubs seem to have recovered well.

The following spring our forsythia bore just a sprinkling of yellow blossoms. That, remember, was the penalty for fall pruning. But as the warm weather unfolded, we were rewarded with vigorous branch growth, healthy green leaves, and attractively shaped shrubs. The next year, our forsythia was ablaze with glorious blossoms. Every plant had survived our fall pruning 18 months earlier.

So if you missed the right-after-bloom window for pruning forsythia, wait until fall and rejuvenate the shrubs.

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